Spain's legislation on automated administrative action is among the most advanced in the world. Enacted in 2007, it has remained the same in the current Administrative Procedure Act of 2015. Currently, more than one third of the Spanish public sector uses these systems. Some problems of compliance with general administrative law remain, such as the right to correct applications, the right to present arguments in the face of a draft before a rejection decision is issued, or the motivation of automated decisions or the transparency of programming. But despite the fact that thousands of automated decisions are taken every day, judicial litigation in this area has so far been merely anecdotal. This paper describes the requirements established by Spanish law for the implementation of automated decision-making systems used by Public Administration: their express prior approval, the auditing of the system, the electronic signature of the decisions, etc.; and the critical aspects that still remain.